Electrical Cable Connection
Electrical Connections
Model
Power Supply
Wiring between indoor unit and outdoor unit
4MXX8509B
208/230V-60Hz, 1 phase
14 AWG / 600 volt / Stranded Wire / 4 Wires
4MXX8512B
4MXX8518B
4MXX8524B
CAUTION
Improper operation may lead to personal injury or property damage.
Size the power supply wiring according to the NEC, local code and the MCA indicated on the unit
nameplate.
1. Always check the unit nameplate for the MCA and MOP requirements.
2. The fuse is located on the main electrical board.
3. The indoor unit must be powered from the outdoor unit. If a disconnect is required by the
Authority Having Jurisdiction (AHJ), a three pole disconnect must be used. Any means of
disconnecting shall meet the approval of the AHJ
4. Install a separate disconnect at the outdoor unit. The power supply, wiring and grounding
of equipment must comply with National, State and/or local codes. The power supply must
match with the equipment nameplate specification.
5. Improperly installed and grounded field wiring poses fire and electrocution hazards. For
high voltage connections, flexible electrical conduit is recommended whenever vibration
transmission may create a noise problem within the structure. To avoid these hazards you
MUST follow requirements for field wiring installation and grounding as described in the
National Electrical Codes (NEC) and your State and/or local electrical codes. All field wiring
MUST be performed by qualified personnel. Failure to follow these requirements could result
in death or serious injury.
6. The wiring, including the ground wire, between the indoor and outdoor units should be at least
14 AWG, 600 volt rated, stranded wire, with an absolute maximum length of 230 ft. (70m).
Shorter lengths result in more robust communication between the indoor and outdoor unit.
Please select an appropriate length for the installation conditions. The wires cannot be cut
and spliced together.
7. For the wired controller: The communication distance between the main board and the wired
controller can be up to 65 ft. (19.8m). The standard distance is 25 ft. (7.6m).
22
Floor and Ceiling Unit
